Field of the Disclosure
The present disclosure relates generally to glass articles and surface treatments for such articles, and more particularly to glass articles that have been surface-treated to exhibit enhanced strength and resistance to surface scratching damage.
Technical Background
Glass surfaces that are not provided with some form of surface protection are highly susceptible to damage from elastic sliding contacts. Such damage, referred to in the art as frictive damage, can range from visible surface scratches to surface flaws that, even if small, can significantly degrade the strength of the glass. Reduced flexural strength as measured by 3- or 4-point flexural modulus of rupture strength testing is one result of such damage.
Susceptibility to frictive damage is not limited to so-called soft (e.g., soda lime) glasses, but is exhibited by harder glasses as well, including but not being limited to the higher-melting aluminosilicate glasses presently preferred for use in advanced displays and other technical applications. Further, tempering methods designed to increase glass strength by developing compressive surface stresses in the glass provide little, or at best only slight, improvements in resistance to frictive damage; thus tempered glasses remain susceptible to such damage.
One known approach for improving the resistance of glass surfaces to flawing that can cause weakening or breakage of glass articles is to apply a protective coating to the glass prior to use. Both inorganic and organic coating materials, including such diverse materials as liquid-applied polymers and vapor-deposited or sintered powder coatings of inorganic compounds or mixtures have been tried. However, while many of these coating methods offer at least short-term protection from sliding contact damage, none of them provides permanent protection nor do any of them effect an improvement in the initial strength of a glass surface to be protected.